Progress Report Two The Lobstars

Keane Tobin, Andy Wilson, Matt Fraser and Kiley DeLong

March 18,2013

The Original Idea

• To create a notification system to identify if the bait

has been removed from a lobster trap

• A spring powered mechanism will release the

buoyant hoop that will float to the surface when the

bait is moved

• This hoop will float up to the surface on the same

rope connected to the buoy

• The ring can be removed easily and will not affect

any of the current processes

Design Updates

• We have gradually modified the features of our

product to arrive at our current design

• Finding a mechanism that fit the criteria proved to be

more difficult then anticipated

• The trigger mechanism and release mechanism

were very difficult to combine but two functioning

prototypes were made

• The material used to create the buoyancy needed

for the hoop was purchased and implemented

First Prototype

First Prototype

• A very rough design of the spring powered

mechanism

• This design used a mouse trap which is triggered by

the bait pin

• The bait pin is attached to the snapper arm of the

mouse trap and when the lobster rigorously pulls on

the bait, the mousetrap is engaged

• This would rotate the the pin and snapper arm which

would release the hoop

First Prototype

First Prototype Flaws

• The mouse trap spring was always in tension

• There was difficultly finding a constant way to initially engage the mouse trap, there was either too much force or too little force

• The rotation of the snapper arm and the bait pin could be impeded by the bait

• Resetting the trap was difficult and time consuming which would not be appealing to lobsterman

• For all these reasons, we discarded this idea

Second Prototype

• After learning from the first prototype, a second

prototype was built

• A wooden box encases the bait pin and the push rod

• The hoop is mounted in the ring clip which is

attached to the outside of the trap

• When the pin is rotated by lobster, it contacts the

push rod which pushes on the ring clip releasing the

hoop

Second Prototype

Second Prototype

Second Prototype Analysis

Second Prototype Analysis

Second Prototype Flaws

• There are less flaws with this design then the

previous prototype

• The lobster may not create enough force to release

the hoop

• If this is a issue, a pre-tensioned spring will be

implemented to compensate for the difference in

force.

The Hoop

• Originally, to make the hoop buoyant, we planned on

using either a spray on foam or wrapping it in

lifejacket material

• A foam tube used for pipe insulation was purchased

and proved to be a better fit to our design

• The hoop was placed inside the tube and it did

create the amount of buoyancy force required

• When the prototype is completed, the hoop will be

spray painted orange for easy identification

The Hoop

Survey

1. Have you every pulled up an empty lobster trap?

• Yes No

2. How often do you pull up empty traps?

• Never Sometimes Often

3. How much time does pulling up these empty trap lose you per day?

• 0-20 mins 20-60 mins More than an hour

4. Would a device to notify you if the bait has been removed from your trap be helpful?

• Yes No

5. Would you be willing to spend an extra 5 mins to add and remove the floating ring in your days work?

• Yes No

6. Would be willing to spend money on this device?

• Yes No

7. Would this device impact your daily fishing schedule?

• Yes No

8. If so would it speed it up or slow it down?

• Speed Up Slow Down

Survey Results

Schedule

Schedule

Conclusions

• Progress has been made in all aspects of our design

• We are very close to having a fully functioning

prototype

• Once this is completed, we plan on doing both on

land and under water testing